2. PARTICLES (From Atoms to Quarks and Leptons) Structure of Matter

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Introduction to Particle Physics (for non physics students) 2. PARTICLES (from atoms to quarks and leptons) Structure of Matter Two ways that structure is revealed: True from atoms to particles….. Spectra Qualitatively similar Spectra Quantitatively different Scattering Nuclear atom Proton/neutron Quarks Qualitatively similar Rutherford: Nuclear Atom Alpha particles from natural radioactivity Gold leaf Small scintillation screen Rutherford used energy conservation… …and long division ..and how Rutherford used them Quarks in the proton Qualitatively: Same idea Quantitatively: Different scale SLAC 3km electron accelerator The BEAM Quarks in the proton Electron beam = 3 km Proton target (hydrogen) Big electronic detector TARGET DETECTOR BEAM me Proton made of 3 quarks, gripped by gluons To make proton and neutron requires two “flavours” of Quarks Up and down Quarks and neutron ddu H atom (not to scale!) a miracle of neutrality electron balances uud hint of unification beta decay at quark level Stars cook the elements Sun is dominantly this first step Heavy elements cooked in stars and ejected into cosmos in supernova explosion Many protons; electrical disruption Stabilised by STRONG force How do we know the neutrino is produced? It hits a nucleus upstream and turns into charged lepton which is detected. Three charged leptons electron muon tau And three neutral: e-neutrino mu-neutrino tau-neutrino Neutrinos and their e-neutrino electron charged partner mu-neutrino muon are always linked tau-neutrino tau if neutrinos are massless BUT if neutrinos have mass, they can oscillate back and forth Neutrino Oscillations • Nu beams from lab (CERN,Fermilab,KEK) • Measure intensity nearby • Measure 100s km away • Evidence that nu are disappearing • Direct evidence for oscillation not yet • Major research programme to understand neutrinos- masses, mixing, key to pattern of the three generations? • Muon-neutrino Nature’s Three Party System Spectra So are quarks (and leptons) also composites? MATTER quarks electron neutrino leptons ANTIMATTER antiquarks ANTIMATTER positron antineutrino antileptons MATTER qqq proton ANTIMATTER ANTIMATTER qqq antiproton leptons MATTER qqq proton BARYONS q MESONS q ANTIMATTER qqq antiproton ANTIBARYONS A Very Short Introduction Coming out in December NEW More in Vsi And particle odyssey The Particle Odyssey TheA Journey Particle to the Heart Odyssey of matter Frank Close, Michael Marten, Christine Sutton .

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Jul/Aug 2013
I NTERNATIONAL J OURNAL OF H IGH -E NERGY P HYSICS CERNCOURIER WELCOME V OLUME 5 3 N UMBER 6 J ULY /A UGUST 2 0 1 3 CERN Courier – digital edition Welcome to the digital edition of the July/August 2013 issue of CERN Courier. This “double issue” provides plenty to read during what is for many people the holiday season. The feature articles illustrate well the breadth of modern IceCube brings particle physics – from the Standard Model, which is still being tested in the analysis of data from Fermilab’s Tevatron, to the tantalizing hints of news from the deep extraterrestrial neutrinos from the IceCube Observatory at the South Pole. A connection of a different kind between space and particle physics emerges in the interview with the astronaut who started his postgraduate life at CERN, while connections between particle physics and everyday life come into focus in the application of particle detectors to the diagnosis of breast cancer. And if this is not enough, take a look at Summer Bookshelf, with its selection of suggestions for more relaxed reading. To sign up to the new issue alert, please visit: http://cerncourier.com/cws/sign-up. To subscribe to the magazine, the e-mail new-issue alert, please visit: http://cerncourier.com/cws/how-to-subscribe. ISOLDE OUTREACH TEVATRON From new magic LHC tourist trail to the rarest of gets off to a LEGACY EDITOR: CHRISTINE SUTTON, CERN elements great start Results continue DIGITAL EDITION CREATED BY JESSE KARJALAINEN/IOP PUBLISHING, UK p6 p43 to excite p17 CERNCOURIER www.
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The Standard Model
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CONTENTS Group Membership, January 2002 2
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The Discovery of the Higgs Boson at the LHC
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Neutrino Physics Was Certainly Major.'Xxii
Neutrino FRANK CLOSE OXFORD UNIVERSITY PRESS OXFORD UNIVERSITY PRESS Great Clarendon Street, Oxford ox2 6dp Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide in Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto With offices in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Thailand Turkey Ukraine Vietnam Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries Published in the United States by Oxford University Press Inc., New York ©Frank Close 2010 The moral rights of the author have been asserted Database right Oxford University Press (maker) First published 2010 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, without the prior permission in writing of Oxford University Press, or as expressly permitted by law, or under terms agreed with the appropriate reprographics rights organization. Enquiries concerning reproduction outside the scope of the above should be sent to the Rights Department, Oxford University Press, at the address above You must not circulate this book in any other binding or cover and you must impose the same condition on any acquirer British Library Cataloguing in Publication Data Data available Library of Congress Cataloging in Publication Data Library of Congress Control Number 2010930302 Typeset by SPI Publisher Services, Pondicherry, India Printed in Great Britain on acid-free paper by Clays Ltd, St Ives ISBN 978-0-19-957459-9 Contents Ray Davis Foreword 1.
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On the Scent of Glue
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